variants: or spiri- or spiro-

Definition of spir-

1 : coil : twist Spiranthes spirivalve Spirochaeta
2 : a chemical compound that contains one or more systems of two rings having a single atom in common with a resulting figure-eight arrangement of atoms spiropentane

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History and Etymology for spir-

Late Latin spir-, from Latin spira

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Cite this Entry

“Spir-.” Dictionary, Merriam-Webster, Accessed 23 Jan. 2021.

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